A tour starts every 15 minutes and you can buy tic...

A tour starts every 15 minutes and you can buy tickets at the counter for a certain time slot. We wanted to take part in the next possible tour and then we only had to wait 45 minutes.
The tour was absolutely worth it.
The guide was involved in the reconstruction of the Semperoper and was able to pass on a lot of background knowledge to us.
Very impressive structure.